You can create a Lookdev view template for your custom shading nodes so that they also appear in the Property Editor with a similar Lookdev view.
Modify your AE<NodeType>Template.xml to include a Lookdev view definition and place the file in the ../.scripts/AETemplates folder of your installation directory. See AEblinnTemplate.xml for an example of how to add the Lookdev view definition. Refer to the section beginning with <view name='Lookdev' template='AEblinn'>.
You can also save the template file to a different location of your choice, and specify the path with the MAYA_CUSTOM_TEMPLATE_PATH environment variable. See Attribute Editor templates.
For more information regarding custom Attribute Editor templates, see Custom Attribute Editor templates.
In addition to creating a Lookdev view template for your custom shading nodes, you can also determine how your nodes appear by customizing the list of attributes displayed for each node type. See Customize a node attribute list in the Node Editor for more information.
The AE<NodeType>Template.xml Attribute Editor template file determines how the Property Editor and the Attribute Editor are displayed.
The NE<NodeType>Template.xml Node Editor template file determines how your nodes appear. For example, NEMyCustomNodeTemplate.xml determines the list of attributes displayed for MyCustomNode in the Hypershade and in the Node Editor. In the Hypershade, MyCustomNode displays with this custom list of attributes when you first create the node. In both the Hypershade and in the Node Editor, MyCustomNode displays with this custom list of attributes in view mode 4.